Bioagent detection using miniaturized NMR and nanoparticle amplification : final LDRD report.

Abstract

This LDRD program was directed towards the development of a portable micro-nuclear magnetic resonance (µ-NMR) spectrometer for the detection of bioagents via induced amplification of solvent relaxation based on superparamagnetic nanoparticles. The first component of this research was the fabrication and testing of two different micro-coil (µ-coil) platforms: namely a planar spiral NMR µ-coil and a cylindrical solenoid NMR µ-coil. These fabrication techniques are described along with the testing of the NMR performance for the individual coils. The NMR relaxivity for a series of water soluble FeMn oxide nanoparticles was also determined to explore the influence of the nanoparticle size on the observed NMR relaxation properties. In addition, The use of commercially produced superparamagnetic iron oxide nanoparticles (SPIONs) for amplification via NMR based relaxation mechanisms was also demonstrated, with the lower detection limit in number of SPIONs per nanoliter (nL) being determined.* Author to whom correspondence should be addressed: tmalam@sandia.gov 4 AcknowledgementsThe progress made in this LDRD project is the result of contributions from a number of team members both here at Sandia National Laboratories, at the University of New Mexico and the company New Mexico Resonance. These members include C. The development and testing of two different µ-coil platforms for nuclear magnetic resonance (NMR) detection were completed under this LDRD project. The performance of these NMR µ-coils allowed the demonstration of SPION (superparamagnetic iron oxide nanoparticle) amplification via induced changes in the NMR relaxation rates of the carrier solvent water. A detection limit of 10 particles/nL was experimentally measured for the first prototype solenoid µ-coil design. These results clearly show that nanoparticle amplification for µ-NMR can be used for detection of bioagents. List of Tables